1. Field of the Invention
The present invention relates to improvement in a photoelectric conversion device which has a plurality of sequentially series-connected semiconductor transducers and its manufacturing method.
2. Description of the Prior Art
As a photoelectric conversion device provided with a plurality of sequentially series-connected semiconductor transducers U.sub.1, U.sub.2, . . . , there has been proposed a structure which comprises (a) a substrate having an insulating surface, (b) a plurality of first electrodes E.sub.1, E.sub.2, . . . formed side by side on the substrate, (c) a non-single-crystal semiconductor laminate member formed on the substrate to cover the first electrodes E.sub.1, E.sub.2, . . . and (d) a plurality of second electrodes F.sub.1, F.sub.2, . . . formed side by side on the non-single-crystal semiconductor layer in opposing relation to the first electrodes E.sub.1, E.sub.2, . . . , respectively, and in which the semiconductor transducer U.sub.i (where i=1, 2, . . . ) is made up of the first electrode E.sub.i, the second electrode F.sub.i and that region Q.sub.i of the non-single-crystal semiconductor laminate member which is sandwiched between the first and second electrodes E.sub.i and F.sub.i, and the second electrode F.sub.i is connected to the first electrode E.sub.i+1 through a contact portion K.sub.i(i+1).
In such a conventional photolectric conversion device, however, the contact portion K.sub.i(i+1), which interconnects the second electrode F.sub.i of the semiconductor transducer U.sub.i and the first electrode E.sub.i+1 of the semiconductor transducer U.sub.i+1, is comprised of, for example, an extension of the first electrode E.sub.i+1 which is formed on the substrate and extends therefrom on the side wall along the direction of arrangement of the semiconductor transducers U.sub.1, U.sub.2, . . . and an extension of the second electrode F.sub.i which is formed on the non-single-crystal semiconductor laminate member and extends therefrom on the side wall along the direction of arrangement of the semiconductor transducers U.sub.1, U.sub.2, . . . and onto the substrate and thence to the extension of the first electrode E.sub.1+1. Therefore, the contact portion K.sub.i(i+1) is complex in construction and there is a certain limit to decreasing the area of the substrate consumed by the contact portions. Accordingly, it is difficult to fabricate the conventional photoelectric conversion device with a simple construction and with a high density.
Further, in the conventional photoelectric conversion device having the above construction, when forming the second electrode F.sub.i which has the extension forming the contact portion K.sub.i(i+1), together with the extension of the first electrode E.sub.i+1, there is a fear of shorting the first and second electrodes E.sub.i and F.sub.i of the semiconductor transducer U.sub.i by the material forming the second electrode F.sub.i. On account of this, it is difficult to obtain a photoelectric conversion device with the desired high photoelectric conversion efficiency.
Moreover, since it is feared that a significant leakage current flows between the first and second electrodes E.sub.i and F.sub.i of the semiconductor transducer U.sub.i through the side wall of the region Q.sub.i of the non-single-crystal semiconductor laminate member extending along the direction of arrangement of the semiconductor transducers U.sub.1, U.sub.2, . . . , there is the likehood that the conventional photoelectric conversion device cannot be operated with the required high photoelectric conversion efficiency.
Various methods have been proposed for the manufacture of the abovesaid photoelectric conversion device.
However, the prior art methods do not allow ease of manufacture of a closely-packed photoelectric conversion device of low leakage current and which achieves the intended high photoelectric conversion efficiency.